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In a 1934 book called "Trees You Want to Know," American botanist Donald Culross Peattie wrote that Atlantic White Cedar would "endure moisture indefinitely," and wood that weathered well was in demand; lots of folks began using it for fencing and roof shingles.

In the late 1800s Atlantic City put up the first large-scale public boardwalk in the United States.

For material they used Atlantic White Cedar, conveniently harvested from New Jersey's nearby forests.

Technically not a cedar at all, but a cypress, the tree grew well in wet areas and was naturally rot-resistant.

Ironically, these excellent properties are what made the wood an unsustainable choice.

Choosing the material to build a boardwalk out of can be tricky.

Never mind the amount of people traipsing over the thing; being located on the shore, it is subject to salt spray.

And in a place with four seasons, the wood is subjected to brutally humid summers and freezing cold winters.

So what did people make boardwalks out of, in the days before pressure-treated lumber?